How to do grafting :
After you have selected a good scion(one year old, w/at least 2 sections of joint above) & cut it (wipe grafting tool cutting blade with alcohol) to perfect fit to root-stock (cambium layer must be contacted well), tying with nursery tape or rubber(must be tight joint point).Tip: use a measuring caliper to find close size diameter branch for scion & root-stock.
Apply the environmental friendly grafting tape over the grafting area, overlap 3 to 4 times, make sure it is tight(air tight: prevent rain/water, bacteria or any other disease from getting into grafting area and keeps the moisture inside the grafting/joint area). Also apply tree seal to cover any new-cut expose area(to prevent infection & keep moisture inside scion/root-stock, very important!!), especially on scion’s tip point, must apply seal to prevent die back effect.
Cover the grafting area with clear plastic bag(spray some filtered water into inner bag area, to keep moisture inside bag, Do not spray water at grafting area). If there is direct sunlight over the grafting area, use brown paper lunch bag to cover it for protection.
After 3 weeks, if the scion still look pretty greenish, then it is great chance that you will see the new bud coming out from scion in 4 to 8 weeks depends on temperature & weather. (Source)